Jimi Green – 3D art and animation student @ Design Centre Enmore

Real world surface properties

The purpose of this exercise is to observe the properties of 3 real work surfaces and make notes for the next step which will be re-creating these surfaces in maya using MIA_X materials.
I choose 3 surfaces that to me had interesting properties to observe –
One is a metal, one is a plastic and another is a combination of glass and liquid.

Surface 1/ Brushed metal (coffee tamper)
Here is reference photo that I snapped of a coffee tamper (used to pack down coffee for use in an espresso machine)

Observations –Colour – this material has an neutral diffuse colour and a low amount of diffuse. Almost all of its perceived ‘colour’ it that of its surroundings reflected.Refraction – there is refraction of light as it is non-transparent.Specularity – there is a fairly high amount of specularity. Light sources are visible reflected in the surface.Gloss – this material has a low glossiness. The light sources diffuse and scatter across the surface due to nature of the brushing. This causes a discontinuous highlight that appears stretched in the direction perpendicular to brushed angle.
The brushing direction loops around the revolved section and changes to straight across on the end caps.transparency – nonetranslucency – noneReflectivity – this material has a high reflectivity.Surface – the surface is generally smooth but has a very shallow perturbance of the surface from the brushing.Surface 2/ Plastic cap-

Observations –Colour – this material has cool pink/magenta hue in its diffuse colour and a high diffuse weight. Reflected light is white in colour.Refraction – some research led to the discovery that these types of plastic have an index of refraction of about 1.5.Specularity – this material has a high specularity. Light sources can clearly be seen reflected in the surface.Gloss – high glossiness, the surface is very smooth and hence reflects light sources very sharply.Transparency – the object has a no real transparency. Light can pass through into the object but nothing can be clearly seen through it.Translucency – the material does have some translucency. It is thin walled and light can pass through it. This is best observed when the object is directly back-lit. Where there are other solid objects i.e the metallic dome and plastic nozzle they block the light and the surface appears darker here than the areas which have a clear path for the light to travel through.Reflectivity – mid-level of reflectivity i.e about half of the light that hits it is bounced back to the eye.Surface – the surface is very smooth and unperturbed.

Surface 3/ Glass honey container

Observations –Colour – the glass has no actual colour, the honey colour is bounced and refracted through the surface.Refraction – The glass has an index of refraction of 1.33. Research has led me to believe that honey bends light slightly more, with an IOR of between 1.48 and 1.51 depending on viscosity and water content. There are complex interactions between the different IORs.Specularity – this material will have a high specularity. Light sources can clearly be seen reflected in the surface.Gloss – high glossiness, the surface is very smooth and hence reflects light sources very sharply.Transparency – this material is highly transparency.Translucency – the glass is totally transparent, but the honey is more translucent diffusing the light as it passes through.Reflectivity – Generally a high level of reflectivity with slightly less reflectivity when seen at a direct angle as opposed from the side observing fresnels law.Surface – the surface is very smooth and unperturbed.